SMAX auxiliary battery problem

Ah, a fellow SMAX owner! I had something very similar happen with my SMAX. The error messages, the hesitant engine start… sounds like a classic auxiliary battery problem. Has it been struggling to hold a charge, especially noticeable with all the electrics these cars have? When the voltage drops too low, the car's power management goes haywire. Is the car struggling when you put it into gear?

Struggling slightly when going into gear, yes. You mentioned low voltage. Did you also measure the voltage? Where did you check it?

I didn't measure it myself, to be honest. With all the complex systems, especially on the hybrid, I didn't want to risk messing something up. Given the symptoms and error codes, plus the struggle when engaging gears, I'd strongly recommend getting it checked at a workshop. It really does sound like the auxiliary battery and the undervoltage issue. Better safe than sorry with these modern systems.

Thanks for the advice. I took it to a workshop; the auxiliary battery was indeed the issue. Repair cost was 290€.